In the process of manufacturing PCBA, soldering is an indispensable process. The pad is easily to fall off in this process, Especially when the PCBA is reworked, this problem is more likely to occur when using the soldering iron.
So what is the reason for the pad to peel off during the soldering process? How to effectively prevent the pad fall off during the soldering process?
Here is an analysis for everyone as bellow:
The reasons of pad fall off :
1: repeatedly soldering a point will lead to the pad fall off;
2: Electric soldering iron solder problem. Generally, the adhesion of the PCB can satisfy with the ordinary soldering, and the phenomenon of pad peeling does not occur. The pad is peeled off is because of the soldering time is too long or the soldering is repeated which cause the temperature to be too high in pcb soldering process. The pad copper expend repeat lead to the pad fall off. However, electronic products are generally subject to rework. Rework is usually repaired by soldering iron. Because the part high temperature of the soldering iron often reaches 300-400 degrees, Causing the local temperature of the pad to be too high for a second, and the resin adhesive under the pad fall off is affected by high temperature. Then the pad peels off.
3: The pressure applied by the soldering iron tip to the pad is too large and the soldering time is too long ;
4: The quality of PCB is too bad.
According to reasons above, it is necessary to avoid the problem of the pad off during the soldering process. When the soldering iron is repaired, the thermal impact on the pad is increased by the thickness of the pad copper foil as much as possible. Drought tolerance and reliability. If want to avoid the problem of the pad fall off of the PCB during the soldering process, and the thermal impact to the pad during the rework using electronic soldering iron. Increase the thickness of the pad copper foil and increase the drought tolerance and reliability of the pad through plating as much as possible. In addition, when selecting the pcb substrate material, you should also choose a high quality manufacturer. Finally, the storage environment of the PCB should be kept dry to avoid moisture.
Is there a way of remedy if the coating and the pad peel off on PCB ?
RAYPCB.COM：The pad drop is unrecoverable, and the flying line is the solution.